he's too busy studying at the 5 or 6 unis he was enrolled at, to go back and see the cops
i think it was in the Uk border force programs, where a Chinese guy was on a 'student visa' for years and his dependent wife 'owned' a take away shop and i think the cops found an illegal worker there
it's time the gov scanned everyone's passport and took a finger print of everyone who enters and leaves the uk, so anyone who's picked up by immigration or the cops, they will know which country to send them back to (it's funny how many have 'lost' their passports), with a long 10yr ban from coming back for being illegal or for committing a crime.